Picrorhiza kurroa

Picrorhiza kurroa is a medicinal herb used primarily for its bioactive phytochemical constituents rather than macronutrient content. Primary Bioactive Compounds (Iridoid Glycosides — collectively termed 'Kutkin', typically 3–6% w/w of dried rhizome): • Picroside I (4-hydroxy-3-methoxycinnamoyl catalpol): ~1.5–3.0% w/w — major hepatoprotective and anti-inflammatory constituent • Picroside II (vanilloyl catalpol): ~1.0–2.5% w/w — considered the principal marker compound; potent choleretic and hepatoprotective activity • Kutkoside (iridoid glycoside): ~0.5–1.5% w/w — contributes to immunomodulatory and anti-inflammatory properties • Picroside III and Picroside IV: trace to minor concentrations (~0.1–0.5%). Other Bioactive Constituents: • Cucurbitacin glycosides (cucurbitacin B, D, and R): trace amounts — contribute to anti-tumor and anti-inflammatory activity • Apocynin (acetovanillone): ~0.05–0.2% w/w — potent NADPH oxidase inhibitor with antioxidant effects; well-characterized pharmacologically • D-mannitol (sugar alcohol): present in small amounts in rhizome • Vanillic acid and related phenolic acids: minor quantities contributing to antioxidant capacity • Androsin (phenolic glycoside): trace amounts. Micronutrients & Minerals (approximate, per dried rhizome): • Iron: ~2–5 mg/100g • Calcium: ~50–120 mg/100g • Magnesium: ~30–80 mg/100g • Zinc: ~1–3 mg/100g • Potassium: ~100–250 mg/100g. Fiber & Macronutrients: • Crude fiber: ~15–25% of dried rhizome • Crude protein: ~5–8% • Total ash content: ~4–7% • Moisture content (dried): ~8–12%. Bioavailability Notes: Picroside II demonstrates moderate oral bioavailability in animal models (~20–30%), with hepatic first-pass metabolism to its aglycone catalpol and vanillic acid. Kutkin (standardized mixture of picroside I and kutkoside, typically 60:40 ratio) shows enhanced absorption when taken with warm water or mild fat-containing vehicles, consistent with traditional Ayurvedic administration (anupana). Apocynin is rapidly absorbed orally with good systemic availability. Standardized extracts (e.g., Picroliv®, standardized to ≥60% kutkin/picroside content) are used in most clinical and pharmacological studies to ensure consistent bioactive delivery. The bitter iridoid glycosides also stimulate gastric acid and bile secretion, which may enhance absorption of co-administered nutrients.